Date of Graduation

Spring 2022


Master of Science in Biology



Committee Chair

Quinton Phelps


The Upper Mississippi River (UMR) supports ecologically and economically important commercial and recreational fisheries. One recreational fishery in the UMR is the Largemouth Bass fishery. Recreational fisheries can be effectively managed using information on population dynamics, though little is known about Largemouth Bass population dynamics in large river ecosystems. Therefore, the objectives of this study were to 1) evaluate recruitment, growth, and mortality of three Largemouth Bass populations in the UMR, specifically within Pools 4, 8, and 13, and 2) to use those estimates of recruitment, growth and mortality to inform exploitation models to evaluate best management practices for each study population. To quantify population dynamics, we studied Largemouth Bass sampled via standard electrofishing as part of the Long Term Resource Monitoring Element (LTRM) of the Upper Mississippi River Restoration Program. From these samples, we collected sagittal otoliths for ageing, and collected length and weight information from each individual. Using the empirical data collected from each fish, we were able to model recruitment, growth, and mortality. Recruitment variability index (RVI) values showed that Largemouth Bass recruitment in Pool 4 (RVI = 0.51) was more variable than that of Pool 8 (RVI = 0.81) and Pool 13 (0.73). However, growth and mortality estimates were varied somewhat among the three study populations. Furthermore, using the dynamic rate estimates as inputs into Fisheries Analysis and Modeling Simulator (FAMS), we developed Yield-per-recruit (YPR) models and models of preferred size fish. YPR models suggest that a more liberal length limit of 279 mm, as opposed to the current 356 mm minimum Length limit, would maximize yield in each pool. Additionally, number of preferred-size fish models suggest that the current 356 mm minimum length limit considerably increased the number of preferred-size fish in each pool under exploitation rates of 20-40%. This information could benefit managers’ decision-making by providing them with information on the Largemouth Bass populations in these recreational fishing areas of interest.


recruitment, growth, mortality, pool, minimum length limit (MLL)

Subject Categories

Aquaculture and Fisheries | Biology | Data Science | Environmental Health and Protection | Environmental Indicators and Impact Assessment | Environmental Sciences | Hydrology | Natural Resources and Conservation | Natural Resources Management and Policy | Physical Sciences and Mathematics | Plant Sciences | Water Resource Management


© Kylie Beth Sterling

Open Access